/*! \page gamess2qmcDoc Gamess to qmc


\section description Description

Basic usage: gamess2qmc -o [outputroot]  [gamess output root] <br>
By default, gamess2qmc will take the last geometry in the .out file and the last set of
molecular orbitals in the .dat file.  This is usually the right
behavior.  GVB wavefunctions are automatically read in.  For CI, see \ref ci
Additional options: <br>
<table>
<tr> <td> Option <td> Description 
<tr> <td> -o [outputroot] <td> Use [outputroot] as the base for the QWalk run.
Gamess2qmc will then create files like outputroot.slater, etc.
<tr> <td> -compare_punch [filename]  <td>  Compares the orbitals in the current punch file to the one specified
here.  Will print what orbitals have changed/rotated, and if any cannot be 
mapped back between the two wavefunctions.
<tr> <td> -virtual [number] <td> Include this number of virtual orbitals into the orb file.  Defaults to 3.
</table>


\subsection ci  Reading a CI determinant

For CI, one has to be careful that the orbitals used by GAMESS to do
the CI expansion are the same ones that QWalk reads in.  This is not
easy for the converter to detect, so you have to take some care
yourself.  The thing to remember is that gamess2qmc always reads the
last set of orbitals in the punch file.  This is almost always the
wrong thing to do during a CI calculation.  Here is a recipe that
generally works, however:
<ul>
<li> Do a Hartree-Fock/DFT/whatever calculation as normal
<li> Use $GUESS to read in the HF orbitals.  For the CI calculation,
  you need to set at least:
  <pre>
 $CONTRL CITYP=GUGA $END
 $CIDRT NPRT=2 NFZC=0 NDOC=1 NALP=2 NVAL=15 IEXCIT=2 $END
 $GUGDIA PRTTOL=0.00001 $END 
</pre>
  NFZC, NDOC, NALP, IEXCIT, and NVAL should all be set according to
  your system.  PRTTOL is the minimum weight that will be available to
  QWalk; you can set the actual cutoff for the determinants in the
  conversion stage.
  <li> Use gamess2qmc to convert the Hartree-Fock calculation and
  gamessci2qmc to read the determinants and their weights from the CI
  calculation.
  <li> Replace the single determinant in the slater file with the
  determinants read from the CI.  Make sure to replace NMO with
  NFZC+NDOC+NALP+NVAL.
  </ul>
An example command sequence could be:
  <pre>
rungms hf >& hf.out
rungms ci >& ci.out
gamess2qmc -virtual 15 -o qwalk hf
gamessci2qmc -wthresh 0.0001 -o qwalk.cidet ci.out
</pre>
  Then construct the ci file as follows
  <pre>
  SLATER 
  ORBITALS {
  CUTOFF_MO
    MAGNIFY 1
    INCLUDE c.basis
    NMO 18
    ORBFILE c.orb
    CENTERS { USEGLOBAL } 
  }
  include qwalk.cidet
</pre>

For small enough cutoff of the determinantal weights, the energy with
  this wave function will match the CI energy.  Often, the QMC energy
  does not need as many determinants to converge, and using
  OPTIMIZE_DET along with a jastrow will improve the convergence in
  determinants within QMC.
  
*/
